There are many towns and cities in the US with extremely low housing costs. Most of West Virginia is a good example as well.
The reason Shreveport always comes to mind when I think of cheap housing is because I always remember that John Carmack and John Romero owned a little lakehouse there and that's where they lived while making Doom.
When Bobby Jindal was running for governor the first time against Kathleen Blanco in 2004, she put out an ad that featured the nappiest, hair sticking up picture of Jindal you could possibly imagine and coupled it with the tagline “Wake up Louisiana, before it’s too late” (implied subtext: and you elect a black man)
I do hear she regretted this on her deathbed stricken with cancer. But more to the point, a friend of mine was at a polling place in Shreveport during that election and witnessed a fistfight between two voters in the parking lot over whether Bobby Jindal was in fact, black or not.
To your point, if more progressive people were willing to live outside of coastal cities, they could affect social change in places like Louisiana.
What it sounds like you are saying is that racism makes towns/cities outside of the coastal areas unlivable. That is simply not true.